NA
NA
NA
1. Field of the Invention
The present invention relates to a drainage cover system for a drain located on the drain of a swimming pool or spa. More particularly, the invention relates to a method and apparatus for preventing the entrapment of a person by the drain of a swimming pool or spa and related injury. More particularly, the invention relates to a method and apparatus for installing a safety swimming pool drain cover in an existing swimming pool. Additionally, the invention relates to a method and apparatus for installing a safety swimming pool drain cover in new construction of a swimming pool.
Swimming pools and spas typically use a pump to drain and recirculate water and supply the filter or supply heated water when a heater is used. Such systems usually have a single main drain or sump located at or near the bottom or lowest part of the swimming pool or spa. In the case of inlets for spas the sump may be in the side of the pool or spa. A portion of the water is normally pumped or suctioned out of the swimming pool or spa through the main drain, into an inlet of a suction pump, and then drained or filtered along with any water from a skimmer and recirculated back into the swimming pool or spa through jets located around the interior walls of the swimming pool or spa.
The drain used in a swimming pools or spa create suction caused by the large volume of water passing through the drain, wherein the suction can be strong enough to trap bathers on the drain. When bathers place their heads or bodies in the vicinity of an active drain, their hair or a portion of their body may become entrapped by the drain, such as at a cover or grating. A blocked drain can develop a strong vacuum within a few tenths of a second. If the suction pressure is strong enough, a bather who is entrapped by a drain may not be able to break free of the suction and may ultimately drown.
Each year, hundreds of young children die and thousands come close to death due to entrapment at a drain in swimming pools and spas. Safety organizations, such as the United States Consumer Product Safety Commission (CPSC), the National Spa and Pool Institute (NPSI), and various state government entities, have acknowledged the need for devices that protect against swimming pool or spa drain entrapment. The CPSC estimates that each year about 300 children under 5 years of age drown in residential swimming pools, and that hospital emergency room treatment is required for approximately another 2,300 children under 5 years of age who were submerged in residential swimming pools. In fact, drowning is recognized as a leading cause of death of children under the age of 5 years in California, Arizona, and Florida. Of particular concern are entrapments involving hair entanglement, limb entrapment, body entrapment, and disembowelment by a drain. Hair entanglement/entrapment occurs when a bather dips below a water surface and his or her hair is sucked into and becomes entangled on a drain grate in the main drain of a swimming pool or spa. Body entrapment typically occurs when part of a bather""s torso completely covers an unprotected or damaged drain, thereby creating a vacuum within the drain from which the bather cannot break free. Limb entrapment refers to accidents in which a bather""s arm or leg is sucked into a main drain of a swimming pool or spa. Disembowelment accidents occur where small children, usually two to six years old, place their buttocks over a drain, covering the drain creating a seal. Injury occurs when the greatly increased suction acts to eviscerate the child when their lower intestines are sucked out of their body through their anus.
Various devices have been used to prevent entrapment, for example, conventional drain systems have used xe2x80x9canti-vortexxe2x80x9d or xe2x80x9canti-entrapmentxe2x80x9d covers, which lack holes at the top, preventing or discouraging a person from covering that hole, and which reduce flow rates (to perhaps less than 6 ft./sec.) to reduce turbulence. Other conventional drain systems for swimming pools and spas have used multiple drains, as opposed to just a single drain, separated by sufficient distance, to prevent a vacuum from being formed when one of the drains is obstructed. Further ways include gravity-fed collector sumps, and vent stacks, which attempt to limit total suction to about 2 ft.-H2O.
A system with multiple drains has its drawbacks, however in that it can be significantly more complex and expensive, especially in retrofit. Additionally, multiple bathers can cover the multiple drains, permitting the creation of the hazardous vacuum, which the system is designed to prevent. Another disadvantage is that the grates or other covers may fail, permitting a person to cover that drain, and become entrapped, or disemboweled. Another is that even grates designed to be xe2x80x9canti-vortexxe2x80x9d or xe2x80x9canti-entrapmentxe2x80x9d may still permit hair entanglement in the drain cover support attachment points or in the cover openings themselves. Yet another disadvantage is that not all swimming pools or spas use the same diameter main drain preventing the use of a single grate or cover in all swimming pools or spas. Further, it is not clear that multiple drains per pump provide sufficient protection because of the potential for dynamic hydraulic imbalance due to debris build up in one of the drains, which may permit a large increase in suction at the other drain.
Pressure detection systems have also been used to reduce the risk of entrapment. Pressure detection systems shut off a drain system when the vacuum pressure within the system reaches a critical level, thus relieving the vacuum at the main drain after a certain time lapse. Unfortunately, the complexity and time delay of such systems raises reliability concerns. Thus, a need still exists for an improved method and apparatus for preventing entrapment.
Newer pools may have a relatively large surface area for the drain cover so that a swimmer can not block enough of flow to be entrapped. These newer drain sumps may be one and one half feet square or two feet in diameter. However, there are many thousands of existing pools and spas that have drain sumps with openings and drain covers less than twelve inches in diameter.
The present invention is primarily directed to retrofitting the thousands of existing pools and spas that do not meet the newer codes and guidelines to prevent swimmer entrapment at the pool or spa drain. It is possible to drain an existing pool and chisel out the concrete around the drain so that a much larger drain sump can be installed that will have a large intake area and large drain cover that can not be blocked by a swimmer. However, the cost of changing the drain sump in a pool and repairing the concrete around the drain sump is substantial.
A better way is needed to retrofit the thousands of existing pools or spas to place them in compliance with newer standards for drain covering sizes that prevent entrapment of a swimmer and drowning. An object of the present invention is to easily and quickly accomplish the retrofitting at a small cost.
2. Description of the Related Art
U.S. Pat. No. 6,360,379 discloses a domed cover for a swimming pool drain that is lockable by a bridge that has upper arms extending downward and lower arms extending upward which are drawn in their respective directions by a bolt that passes through threaded upper and lower hubs. The bridge has bearing feet pivotally connected between the adjacent facing ends of the arms that, once extended, exert pressure against the inside surface of the drain. The bolt passes through the center of the domed cover with an exposed bolt cap to allow for rotating the bolt, extending the arms and locking the cover in place.
U.S. Pat. No. 6,088,842 discloses a drain structure for a pool or hot tub that has normally present suction or drain forces. The drain has a plurality of interior grating members, which are cantilevered from the inner wall and tapered lower releases surfaces, designed to alleviate or eliminate hair entanglement or vacuum problems with the body. The drain surfaces facilitate the release of hair strands that may become entangled or knotted due to the vacuum of the drain. In another embodiment the interior gratings may have sharp cutting edges designed to sever or snap the entangled or knotted hair strands.
U.S. Pat. No. 5,978,981 discloses a device to for hair control that includes a grate with a plurality of elongated flow channels isolated from each other, and is installed into the pump inlet of pools and spas. The channels are designed to decrease turbulence and prevent hair from entangling or knotting behind the grate in such a manner that a person""s head would be held under water. The channels of the grate are at least 18 inches long and can be linear or in a helical pattern.
U.S. Pat. No. 6,009,573 discloses a safety diffuser that is used with the suction inlet of a pool or spa, consisting of a tubular portion that is sealed to the suction inlet and has strategically placed holes designed to prevent the user of the pool or spa from being able to block all of the holes and be drawn to the device and held underwater, thereby reducing the danger of drowning.
U.S. Pat. No. 6,393,631 discloses a pool drain safety cover system and method. The system consists of a base with at least one primary fluid aperture and a plurality of secondary apertures. The cover also includes a grate that extends across, at a minimum, the primary fluid aperture, to allow the drain water to pass through it. The grating has at least an upper and a lower layer which are adjacent to each other and are each comprised of a plurality of spaced ribs to allow drain water to pass through. The invention also includes a method describing the same. The cover is described as being attached by any chemical or mechanical means including adhesives, screws or nails.
U.S. Pat. No. 6,397,408 discloses a ramped cap unit for installation over the main drain of a swimming pool. The cap unit is equipped with an upstanding anti-vortex safety drain cover, wherein the ramped cap unit is shaped in a manner to allow a pool cleaner to travel over and across it without interruption or disruption. The cap unit comprises a generally inverted saucer defining a ramped surface having a diametric size to fit over the safety drain cover. An array of ribs formed on the underside of the cap unit engage an outer periphery of the upstanding drain cover to retain the cap unit in position on the drain cover. A large plurality of holes are formed in the cap unit at spaced-apart locations to permit downward water flow therethrough substantially without disrupting the anti-vortex and safety functions of the drain cover it is in position over.
U.S. Pat. No. 6,340,035 discloses an anti-vacuum cover defined by a centrally supported grating together with at least one outwardly extending tributary tube through which fluid may pass if the grating is obstructed. The outboard end of the tributary tube may be shaped in any fashion so as to prevent one from being able to block it with ones hand. The grating may further incorporate cantilevered elements so as to prevent hair entanglement by allowing any entangled or knotted hair to simply slide over the element and out of the drain. The tributary tubes are described as being at least 18 inches long and either straight or curved to minimize hair entanglements and have the ends far enough away from the grate so that it prevent one from being able to block all openings to the drain with ones body. The tributary tubes may also direct the flow of fluid so as to be opposite of the flow of the vortex and aid in the counter effects of a vacuum. The invention is disclosed as being held in position by screws.
U.S. Pat. No. 5,734,999 discloses a floor drain grate that including two to three separate regions through which water can flow into the drain. The regions are spaced-apart, preferably one to two feet, to effectively prevent a swimmer from covering all openings simultaneously, preventing suction entrapment. One or more elongated channel portions are used to create a flow passage structure to space apart the inflow regions, and a central portion overlies the drain, and provides a further inflow region. The floor drain grate, including the channel portions, is disclosed as overlaying the pool floor. The central portion is disclosed as being integrally formed with the central portion, is as being attached thereto using screws or adhesives.
U.S. Pat. No. 3,940,807 discloses a outlet drain for a spa including channels extending radially substantially in all directions from the central drain aperture through which water can enter the drain. The channels extend approximately two feet, from the ends of opposing channels, to effectively prevent a swimmer from covering all of the channels simultaneously, preventing entrapment. It also discloses an anti vortex plate covering the drain sump. The drain is disclosed as being able to be integrally molded with or bonded to the bottom of the pool, or to replace the existing drain in a pool or spa. The vortex plate is disclosed as being held in position by screws, and the retrofittable drain is held in place by spring clips that apply a downward force to pride a secure fit and to prevent unintended removal.
U.S. Pat. No. 6,170,095 discloses a main drain safety grate apparatus that utilizes an elongate drain, frame and grate that distributes the suction flow of water over a large surface to avoid full blockage of the grate, and also utilizes a bendable or deformable, upwardly releasable grate that has a section slotted to permit water to drain therethrough. The grate is ordinarily restrained from upward movement by a slot in each end of the frame into which the ends of the grate fit, and from downward movement by two shelves on which the grate may be supported. The grate may be released from the frame by an upward farce applied at the section provided for drainage, which bends, or bows, the grate in an arcuate shape, and acts to shorten the length of the grate relative to the slots into which it is fitted. The bowing effect also serves to rotate a rounded surface and a corner of the end of the grate so as to reduce the effective length by rotating the corner away from the point of contact of the slot and the grate, and permitting that contact point to move over the rounded surface and effectively breaking away freeing anyone whose hair or other body part may have become entangled or entrapped. The apparatus is disclosed as being implemented during the construction of the pool.
U.S. Pat. No. 5,809,587 discloses a safety device for use in a suction outlet assembly of a swimming pool, whirlpool or spa or the like that consists of a cover mounted over the opening without substantially obstructing the flow of water and an obstructing mechanism for obstructing an opening in communication with the main drain pump of the swimming pool, whirlpool spa or the like if the cover is not properly positioned or affixed to the outlet assembly. If the cover does become dislodged or is no longer properly positioned, the obstructing mechanism, consisting of a plunger and a flapper valve which is pivotally mounted to the assembly, will move from opened to closed position, thereby blocking the flow of water and preventing the suction of a body or hair into the suction outlet.
U.S. Pat. No. 6,295,661 discloses an automatic shut off valve for installation in a swimming pool or spa main drain. The automatic shut off valve consists of a soft gasket, ball and ball spring between a grate and a housing. The grate is free to reciprocate up and down relative to the housing. Downward reciprocation of the grate urges the ball into sealable engagement with a valve seat in the housing. During operation, a swimmer covers sufficient grate apertures so that the grate is moved downwards as urged by the main drain suction. The downward motion of the grate urges the ball into sealable engagement with a valve seat in the housing where it is securely held by the main drain suction. In this fashion the ball is entrapped instead of the swimmer, thus avoiding harm to the swimmer. If the grate and ball should become dislodged a spring-loaded cap is pivotally attached to the housing and swings down urged by the main drain suction thereby effectively sealing off the drain and preventing any suction related injuries. The automatic shut off valve is disclosed as being held in place by screws.
U.S. Pat. No. 6,408,452 discloses an automatic shut off valve for installation in a swimming pool or spa main drain. The automatic shut off valve consists of a ball and ball spring between a diaphragm and a housing. The diaphragm is made of resilient material and is free to reciprocate up and down relative to the housing. Downward force on the diaphragm urges the ball into sealable engagement with a valve seat in the housing. During operation, a swimmer covers sufficient diaphragm apertures so that the diaphragm center is moved downwards as urged by the main drain suction. The downward motion of the diaphragm urges the ball into sealable engagement with a valve seat in the housing where it is securely held by the main drain suction. In this fashion the ball is entrapped instead of the swimmer, thus avoiding harm to the swimmer. A back-up shut off function is provided by a cap spring-loaded into a closed position whence it migrates shout the ball and diaphragm become dislodged. The automatic shut off valve is disclosed as being held in place by screws.
U.S. Pat. No. 6,038,712 discloses a suction assembly for use in whirlpool baths and the like that employs an air induction tube to induct air into the recirculating water pump to cease pumping operation when the face of the assembly is blocked. The induction tube is connected to a bleed path formed between the induction tube and a surrounding coaxial face tube extended into the assembly and empties the induction tube. Air is then pulled into the pump, causing the pump to lose prime thereby reducing pump pressure to zero and allowing the hair or other blocking material to be removed. In a preferred embodiment, the induction tube is connected to the air inlet of at least one venturi-type hydromassage jet assembly. The suction assembly employs a spring-loaded induction stem, which bears compressively against the interior face of the suction cover, thereby permitting use of conventional suction covers. The suction assembly discloses that the front face is attached to the assembly by screws.
U.S. Pat. No. 5,822,807 discloses a suction relief apparatus for relieving suction at a suction connection of a swimming pool or spa having a main valve member movable from an open to a closed position to relieve suction at the suction connection in the event of a blockage of the suction connection in the pool. The main valve remains closed until a reset valve is opened, at which time a spring returns the main valve to the open condition, enabling suction to resume at the suction connection of the pool.
U.S. Pat. No. 6,341,387 discloses a vacuum elimination device that entails a xe2x80x9cTxe2x80x9d-type connection installed on the suction line from between the recirculating pump system and the main drain of a swimming pool. Involved is an interior vertical pipe fluidly connected to the main drain suction line via the xe2x80x9cTxe2x80x9d-type connection opening downward which is enclosed within an exterior vertical pipe of larger diameter that is closed at the bottom and vented to the atmosphere at the top. The configuration of vertical pipes creates a column of water that is vented to the atmosphere during normal operation, but when the main drain is blocked the recirculating pump evacuates the column of water finally drawing only air from the vented opening causing the recirculating pump to lose prime and release the blockage.
U.S. Pat. No. 6,269,493 discloses a break away drain cover for a spa employing a drain cover with a magnet attached to it and a magnetically actuable reed switch, so that once the drain cover breaks away or is removed it will cause the reed switch to change state which opens a circuit controlling the operation of the spa circulation system. As a result, the spa circulation system cannot operate without the drain cover attached, reducing the chance that a spa user might be harmed if the user""s hair becomes entangled in the drain cover.
U.S. Pat. No. 5,894,609 discloses a system for periodically removing the suction source from each drain in a pool or tub so that one sitting on a drain can readily remove himself from the drain whenever desired. The system is designed to alternate the suction for the pool or tub drains by alternating the suction from one drain to another. The is accomplished by either mechanically rotating drain pipes or by electronically turning on or off the pumps via a timer.
U.S. Pat. No. 5,690,476 discloses an electrical circuit adapted to shut-off power to a water reservoir pump whenever the drain becomes blocked. The electrical circuit comprises a vacuum-operated switch that opens the circuit whenever a partial vacuum draw or a predetermined pressure is experienced.
U.S. Pat. No. 6,003,165 discloses an electrical circuit adapted to shut-off power to a water reservoir pump in a portable spa whenever the drain becomes blocked. The electrical circuit comprises a vacuum-operated switch that opens the circuit whenever a partial vacuum draw or a predetermined pressure is experienced on the drain of the portable spa.
The present invention relates to a new and improved safety device, which overcomes the problems and disadvantages of the prior art discussed above. More particularly, the safety device is adapted for use in the main drain of an existing swimming pool, spa or the like. The safety device is designed to replace the standard small drain covers on drain sumps of existing pools or spas to make the drains safer and help avoid entrapment of a swimmer on the older pools.
In accordance with the invention an installation plate is provided for determining the proper placement of the drain cover or cover plate and adapter ring for a swimming pool or spa in a position covering the main drain with the purpose of effectuating a proper seating of the anti-entrapment drain cover. The installation plate is substantially the same diameter and size as the drain cover with the exception of an opening defined by a three lobed hole in the center. The opening allows for access to the stainless steel adapter ring bolts during installation. After installing the adapter ring the installation disk is removed and the drain cover is attached to the adapter ring. Once the drain cover is attached, a swimmer can not access them to loosen them so the adapter ring remains firmly in place.
In a preferred configuration, the drain cover has a disc shape having a diametric size and shape to rest on the swimming pool or spa floor and extend well beyond the opening of the main drain sump, for the purpose of providing a large enough surface area so as to prevent a bather from blocking the entire drain and creating a seal on the main drain by placing his or her body on it. A large plurality of spacer ribs or ribs formed on the underside of the drain cover extend radially from the center out to the edge of the drain cover. Each ridge is equidistance from neighboring ribs to allow for fluid movement under the disc once the ribs are resting on the pool bottom surface surrounding the main drain of the swimming pool or spa. The ribs vary in length alternating between longer and shorter ribs providing the greatest flow of water under the drain cover. A large plurality of small, circular holes or holes permeate the entire surface of the disc excluding a circular area, the diameter of which is greater than that of the main drain, immediately at the center of the drain cover to permit downward flow therethrough substantially without disrupting the safety function of the solid center portion of the drain cover. The drain cover utilizes a adapter ring with three equally spaced threaded stainless steel bolts that extend through the ring, from the center outward, for the purpose of extending to lock the ring in place within the main drain sump. The adapter ring acts as a universal mount for the drain cover, so as to fit any typical diameter drain sump. The adapter ring when installed in the drain allows fluid, once it has passed through and around the drain cover, to flow through its open center and around the outsides between the ring and the drain wall. The adapter ring may be installed at an angle to allow for the drain cover to lay flush on the pool bottom. The drain cover is finally securely joined with stainless steel tamper proof screws to the adapter ring so that the drain cover cannot be dislodged on accident or by mischief.
When the drain cover includes an installation opening in the center it can be used in lieu of an installation plate for installing the adapter ring in a drain sump. A small cover would be installed with the drain cover to cover the installation opening after the adapter ring is secured in place.
It is an object of the invention to provide a safety drain cover apparatus and method for an existing swimming pool drain to protect a swimmer from entrapment.
It is an object of the invention to provide a method for installing a safety drain cover in an existing swimming pool drain to protect a swimmer from entrapment.
It is an object of the invention to provide a drain sump adapter ring and drain cover that can be easily secured into an existing pool drain sump.
It is an object of the invention to provide a drain sump adapter ring and drain cover that can be easily secured into an existing pool drain sump without having to drain the pool.
It is an object of the invention to provide an installation plate and method for positioning a adapter ring in an existing pool drain sump.
It is an object of the invention to provide an anti-entrapment drain cover for an existing pool that has sufficient cross sectional area so that the velocity of flow though the drain cover at any point on the drain cover even if partially blocked by a swimmer and at any point on the drain cover when there is no blockage is at a rate to protect a swimmer from entrapment.
It is an object of the invention to provide an installation plate with the same diameter and size as the drain cover to position the adapter ring at the correct position in an existing pool sump.
It is an object of the invention to provide an installation plate with an access opening to allow access to adapter ring securing means to allow securing of the adapter ring at the correct position in an existing pool sump.
It is an object of the invention to provide an anti-entrapment drain cover for an existing pool with sufficient cross sectional area and flow rate so the velocity of flow though the drain cover is less than about 1.5 feet per sec flow at any point on the drain cover even if as much as 20% blocked by a swimmer to protect a swimmer from entrapment.
It is an object of the invention to provide a adapter ring for an existing swimming pool drain sump that has means to allow water to flow around it when positioned in a drain sump to allow water to flow out a pool drain pipe.
It is an object of the invention to provide a new drain cover for an existing pool that will not trap a swimmer""s hair.
It is an object of the invention to provide an anti-entrapment drain cover for an existing pool with sufficient cross sectional area and flow rate so the velocity of flow though the drain cover is in the order of 1.5 feet per sec flow at any point on the drain cover even if partially blocked by a swimmer.
It is an object of the invention to provide a method and apparatus for securing a adapter ring in an existing pool drain sump so the adapter ring is in the correct position in the pool drain sump for a supporting an anti-entrapment drain cover.
It is an object of the invention to provide a method and apparatus for modifying an existing swimming pool drain so that it allows flow of water through the drain cover in the order of 1.5 feet per see flow at any point on the drain cover even if partially blocked by a swimmer.
Other objects of the invention will be apparent from the following detailed specification.